This invention relates generally to protective hoods, and more particularly, to protective hoods for protecting a wearer against hazardous environmental elements.
Firefighters, rescue workers, civilians, and others working in chemical, biological, nuclear, and other environments sometimes use protective hoods to protect their heads from chemical, biological, radiological, nuclear, or other contaminants that may be present in the environment. A protective hood typically includes a protective head covering that is capable of being attached to a source of breathing air (such as, but not limited to, a powered air-purifying respirator (PAPR) and/or a pressurized air supply), and an adjustable head harness for securing the protective hood on the wearer's head. It is desirable that the protective hood be securely donned on the wearer's head to prevent the environmental contaminants from being exposed to the wearer's head and thereby putting the wearer at risk. It may also be desirable that the protective hood is “one size fits all”, i.e., the protective hood securely and comfortably fits a variety of different head sizes.
To provide a protective hood that fits a variety of different head sizes, some known protective hoods use adjustable head harnesses that include hook and loop fasteners, while other known protective hoods include adjustable head harnesses that include a headband and a ratchet assembly for adjusting the size of the headband. However, the hook and loop fasteners and the ratcheting headband may require multiple re-adjustments to achieve a secure and comfortable fit. Moreover, because the hook and loop fasteners and the ratcheting headband are typically held within an interior space of the protective hoods, it may be difficult to re-adjust the harness once the protective hood has been donned. Accordingly, achieving a secure and comfortable fit may require the wearer to repeatedly don and remove the protective hood. Also, once the wearer has been exposed to hazardous environmental elements, the wearer may not be able to easily adjust the fit of the protective hood without removing the hood and thereby exposing the wearer's head directly to the hazardous environment. Hook and loop fasteners and ratcheting headbands may also add additional components to the adjustable head harness, which may increase the cost of manufacturing the protective hood. Adjustable head harnesses having ratcheting headbands may also be more bulky, which may increase a size and/or a complexity of a package containing the protective hood.
Some other known protective hoods use adjustable head harnesses that include an elastic band attached to an interior surface of the protective hood. However, the elastic bands used in some adjustable head harnesses are fabricated from latex. Because the latex elastic band is attached to an interior surface of the protective hood, contact between the latex elastic band and the wearer's head may present a hazard to wearer's who are allergic to latex.
There is a need for a protective hood having an adjustable head harness that overcomes one or more of the problems described above.